For the mass production of large, severe aspherical optics, we have developed a new stitch algorithm named ARSA (Approximated Reference Shape Algorithm) which can be used for free-form measurement machines. The stitching measurement, which combines plural partial measurements into a whole shape, has been developed based on interferometry and is now widely used. The well known algorithm calculates the stitching parameters so as to minimize the mismatch in the overlapping area. However, with a free-form measurement machine using a scanning probe, the measured data are sparse and contain 3D points, causing significant calculation errors such as interpolation errors in the overlapping area. ARSA is based on minimizing the error of estimating the approximated reference shape. This algorithm has the unique feature that the calculation error is smaller in the case of severer asphericity and the interpolation error is also small for the same reason as in the case of interferometry. We classify the workpiece's shape into three spatial frequency domains and assess the performance for each case by simulation. The simulated measurement data are three sets of 3D points in fan-shaped partial measurements, and the workpiece's shape is a convex hyperboloid whose asphericity is 1.282mm for the full aperture of 1200mm. In all three domains the calculation results coincide with the theoretical values to within nanometer level. These results show the validity of this new algorithm.

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Ultra-precision machined surface such as semiconductor wafer are highly demanded nowadays. However, because of shrinking design rules of the semiconductor, it is uprising the difficulty of detecting nano-defects. To keep process yield in manufacture line, we must develop a defect measurement system with higher resolution, throughput, non-destructiveness and robustness. As such a measurement system, we have proposed the application of the structured light illumination (SLI) microscopy. The proposed method is optical inspection system and that resolution exceeds the diffraction limit. Conventional proposed method has a difficulty about imaging system. Despite the imaging system is coherent system, the imaging system required in conventional super-resolution algorithm is incoherent system. In third report, we propose new super-resolution algorithm based on coherent imaging system, and three-light-flux interference standing wave illumination that enables new algorithm usage. To verify new proposed method, we carried out computer simulation comparing new method and conventional method. As the result, superiority of new method is confirmed. And improvement of new method robustness by increasing standing wave shift times is also confirmed.

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The objective of the present research is to conduct a trial production of an aerostatic lead screw system, in which all moving parts are supported by aerostatic bearings made of molded resin and to evaluate how much performance is achieved in this low cost system. Epoxy based resin available for slideway coating was used to make all bearing surfaces by means of casting or molding technique which is known to be able to produce complex shapes with low cost. The motion accuracy of the produced nuts was evaluated by measuring the straightness of straight line motion and the positional deviation. The results showed that the straightness was 0.15μm and the deviation was 3 to 4μm in the working distance from 0 to 60 or 84mm, which was almost same as the cumulative pitch error of the screw shaft. The nut positional deviation per one revolution was 2 to 3μm as a result of the 1.5μm axial travel variation of the screw and the 0.2μm axial run-out of the screw shaft. The slightly larger positional deviation of the nuts may be due to the low bearing stiffness of the nuts.

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Hydrostatic bearing is often employed as a guideway of grinder for cam shaft and crank shaft, which are required to achieve both of high accuracy and high productivity. Reduction of bearing pocket is effective in driving down manufacturing cost of the guideway. In this research, hydrostatic bearing with self-controlled restrictor is proposed to achieve demand performance by less bearing pockets than those of conventional guideway with orifice restrictor. A self-controlled restrictor with a diaphragm improves static stiffness of the proposed bearing. Dynamic stiffness and step response are calculated by numerical analysis based on Reynolds equation, which considers non-linearity of oil flow at restrictor, elastic deformation of plumbing and volumetric strain of air bubble in oil. The analysis results have revealed that the important parameters for static stiffness of hydrostatic bearing would be the gap of the diaphragm restrictor, thickness of diaphragm and supplied pressure of bearing oil. Dynamic stiffness depends on air amount in oil and length of plumbing. The developed bearing has achieved three times higher stiffness in static response than that of the conventional bearing with orifice restrictor. Dynamic stiffness has also improved at the range of low frequency.

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Development of excretion support device is crucial in order to help the elderly and disabled become independent and reduce the burden on caregivers. The act of eliminating waste touches on individual dignity. Thus, the ability to perform this action independently is important for an individual to maintain self-respect. The objective of this study is to develop a system to support independent waste elimination for the handicapped persons on the upper limbs. Eliminating waste requires comprehensive support including removing clothes and transfer motion. In this study, however, we focus on cleaning up after eliminating wastes, which requires special psychological consideration, and an attempt to develop a device that assists with this task. In this paper, we propose a mechanism for an end effector with multiple fingers capable of gripping and passing toilet paper. We show an action to clean the genital area by causing the end effector to contact the buttocks using an arm actuator, while moving the end effector forward and rotating. In addition, we propose a mechanism for removing and collecting used paper. We achieved an 88% cleaning rate in motion experiments using simulated buttocks. These experiments demonstrated the effects and issues of the device.

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For construction of the service system in the public accommodation, for example museums, art galleries and so on, we propose a method to relate attribute information to each trajectory of the one who has RF tag. Specifically, at first the trajectories of the people are measured from the video captured from a fixed camera. Next, the trajectories are combined with attribute information obtained from UHF band RFID system according to on-off pattern of each RF tag readability. To verify the proposed method, some experiments were performed in a large space which is assumed as public accommodation. As the result, in the first 1 sec from the start of measurement, the accuracy rate exceeds 75%. Moreover, it exceeded 90% in the first 6 sec and it reached to 100% in the first 8 sec.

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A burr has been basically defined as a thin ridge or area of roughness produced in cutting or shaping metal. This burr leads to an undesirable workpiece edge that must be removed to enhance the level of precision of the parts. However, the cost of deburring precision components can be a significant addition to the cost of the finished parts. This paper presents a basic framework for a burr prediction system in end-milling based upon burr formation models, cutting condition, and analytical cutting force models. We developed a representation in a CAD framework to illustrate the machining process upon a PC-based NC simulator. This NC simulator can predict burr dimension and location in the end-milling process as a preventive measurement method. In addition, a tool paths planning scheme was included in the system to avoid tool exits. This method provides a feasible way for suppressing exit burr formation in an automatic manner, and thus reduce the need for deburring. The effect of in-plane exit angle was also discussed in this study. A systematic comparison of the predicted and measured burr size over a wide range of cutting conditions confirms the validity of the proposed method.

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The purpose of this study was to clear the conditions for good performance in dry cutting of aluminum alloys with non-hydrogenated diamond-like carbon (DLC) coated tool. The intermittent and continuous cutting tests were conducted under dry condition to 4 types of aluminum alloys. Consequently, it was found out that DLC coated tool showed good performance in intermittent cutting of A5052 and A7075 (Wrought aluminum alloys), but it didn't show good performance in intermittent cutting of AC2A and AC8A (Aluminum castings) and in continuous cutting of A5052 and AC2A. It was thought that the disappearance of DLC coating on the tool rake face caused adhesion in cutting of aluminum castings and continuous cutting of wrought aluminum alloys.

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